1. Field of the Invention
This invention relates to a continuously variable automatic transmission for motorized vehicles including heavy trucks, buses as well as light automobiles. The transmission includes a hydraulic device such as, but not limited to, a hydraulic torque converter and one or more planetary gear assemblies operatively interconnected to one another and connected in a predetermined manner to the output of the vehicle engine and the hydraulic device so as to accomplish the variable transmission of torque to the driving wheels of the vehicle.
2. Description of the Related Art
A typical automatic transmission usually comprises a hydraulic torque converter, a planetary gear ensemble, some brake devices and a control system, for transmitting a torque generated by an internal combustion engine to the driving wheels, wherein the torque is usually transmitted in several stages.
A more recently developed transmission generally includes a set of adjustable pitch pulleys in cooperation with a belt for variably transmitting the torque from drive engine of the vehicle to the driving wheels thereof. Belt structures of the type referred to have been improved several times in order to provide a better resistance against breaking and wear. However, only a limited torque transmission is capable of using such technology.
According to the present invention, the torque generated by the vehicle engine is transmitted to the driving wheels by combining the operative features and components of an automatic transmission with the performance and benefits of a continuously variable transmission. As a result the preferred embodiments of the variable automatic transmission of the present invention are suitable for use on heavy duty trucks as well as lighter automobiles. Moreover, the results in doing so include an improve fuel economy, a reduction in emissions from engines exhaust gasses, lower production and maintenance costs and an increased durability.